We are moving are web servers from a datacenter to Azure. The DNS provider will stay the same, but we will be using a CNAME record to point to Cloudflare so we can take advantage of the WAF capability only. The Authoritative DNS will remain the same.
My question is about the A record.
Current set up:
We will ask to have the CNAME record to point to our cloudflare account, which will then use Cloudflare to point to the Azure traffic manager. No problem.
But what about the A record? We will need to change the IP the A record points to. The night we move to Azure, we want to point the A record to a new IP in Azure. While DNS updates, will the CNAME look ups fail since it is being changes from the old IP at the data center to the new IP in Azure.